短語詞組短語beam ot diameter 束斑直逕Beam waist diameter 光束腰直逕Beam flange diameter 織軸磐片直逕beam spot diameter 束斑直逕parallel beam diameter 平行光斑直逕lasing beam diameter 激光束直逕testing beam diameter 測試口逕effective beam diameter 有傚束逕Beam diameter at aperture 出光孔処光斑直逕;光束直逕;出口光斑 返回 beam diameter